From 0819616be7c980481cd570ce39448d84408d7859 Mon Sep 17 00:00:00 2001
From: patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>
Date: Tue, 28 Feb 2012 21:58:24 +0000
Subject: Add support for C++ static constructors (at least to a few platforms)

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4438 42af7a65-404d-4744-a932-0658087f49c3
---
 apps/examples/README.txt       | 13 ++++++--
 apps/examples/helloxx/main.cxx | 73 +++++++++++++++++++++++++++++++++++-------
 2 files changed, 71 insertions(+), 15 deletions(-)

(limited to 'apps/examples')

diff --git a/apps/examples/README.txt b/apps/examples/README.txt
index a89a9097c..fb947cd71 100644
--- a/apps/examples/README.txt
+++ b/apps/examples/README.txt
@@ -362,12 +362,19 @@ examples/helloxx
   library suupport is available, and that class are instantiated
   correctly.
 
-  NuttX configuration settings:
+  NuttX configuration prerequisites:
+
+    CONFIG_HAVE_CXX -- Enable C++ Support
+
+  Optional NuttX configuration settings:
+  
+    CONFIG_HAVE_CXXINITIALIZE -- Enable support for static constructors
+      (may not be available on all platforms).
+
+  NuttX configuration settings specific to this examp;le:
 
     CONFIG_EXAMPLES_HELLOXX_BUILTIN -- Build the helloxx example as a
       "built-in"  that can be executed from the NSH command line.
-    CONFIG_EXAMPLES_HELLOXX_NOSTATICCONST - Set if system does not support
-      static constructors.
     CONFIG_EXAMPLES_HELLOXX_NOSTACKCONST - Set if the system does not
       support construction of objects on the stack.
 
diff --git a/apps/examples/helloxx/main.cxx b/apps/examples/helloxx/main.cxx
index ed48f4961..8514fead2 100644
--- a/apps/examples/helloxx/main.cxx
+++ b/apps/examples/helloxx/main.cxx
@@ -1,8 +1,8 @@
 //***************************************************************************
-// examples/helloxx/main.c
+// examples/helloxx/main.cxx
 //
-//   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
-//   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+//   Copyright (C) 2009, 2011-2012 Gregory Nutt. All rights reserved.
+//   Author: Gregory Nutt <gnutt@nuttx.org>
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
@@ -38,13 +38,39 @@
 //***************************************************************************
 
 #include <nuttx/config.h>
-#include <nuttx/init.h>
+
 #include <cstdio>
 #include <debug.h>
 
+#include <nuttx/init.h>
+#include <nuttx/arch.h>
+
 //***************************************************************************
 // Definitions
 //***************************************************************************
+// Debug ********************************************************************
+// Non-standard debug that may be enabled just for testing the constructors
+
+#ifndef CONFIG_DEBUG
+#  undef CONFIG_DEBUG_CXX
+#endif
+
+#ifdef CONFIG_DEBUG_CXX
+#  define cxxdbg              dbg
+#  define cxxlldbg            lldbg
+#  ifdef CONFIG_DEBUG_VERBOSE
+#    define cxxvdbg           vdbg
+#    define cxxllvdbg         llvdbg
+#  else
+#    define cxxvdbg(x...)
+#    define cxxllvdbg(x...)
+#  endif
+#else
+#  define cxxdbg(x...)
+#  define cxxlldbg(x...)
+#  define cxxvdbg(x...)
+#  define cxxllvdbg(x...)
+#endif
 
 //***************************************************************************
 // Private Classes
@@ -53,11 +79,20 @@
 class CHelloWorld
 {
   public:
-    CHelloWorld(void) : mSecret(42) { lldbg("Constructor\n"); };
-    ~CHelloWorld(void) { lldbg("Destructor\n"); };
+    CHelloWorld(void) : mSecret(42)
+    {
+      cxxdbg("Constructor: mSecret=%d\n", mSecret);
+    }
+
+    ~CHelloWorld(void)
+    {
+      cxxdbg("Destructor\n");
+    }
 
     bool HelloWorld(void)
     {
+        cxxdbg("HelloWorld: mSecret=%d\n", mSecret);
+
         if (mSecret != 42)
           {
             printf("CHelloWorld::HelloWorld: CONSTRUCTION FAILED!\n");
@@ -68,7 +103,7 @@ class CHelloWorld
             printf("CHelloWorld::HelloWorld: Hello, World!!\n");
             return true;
           }
-    };
+    }
 
   private:
     int mSecret;
@@ -78,7 +113,10 @@ class CHelloWorld
 // Private Data
 //***************************************************************************
 
-#ifndef CONFIG_EXAMPLES_HELLOXX_NOSTATICCONST 
+// Define a statically constructed CHellowWorld instance if C++ static
+// initializers are supported by the platform
+
+#ifdef CONFIG_HAVE_CXXINITIALIZE 
 static CHelloWorld g_HelloWorld;
 #endif
 
@@ -105,20 +143,31 @@ extern "C" int helloxx_main(int argc, char *argv[]);
 
 int MAIN_NAME(int argc, char *argv[])
 {
-#ifndef CONFIG_EXAMPLES_HELLOXX_NOSTACKCONST
-  CHelloWorld HelloWorld;
+  // If C++ initialization for static constructors is supported, then do
+  // that first
+
+#ifdef CONFIG_HAVE_CXXINITIALIZE
+  up_cxxinitialize();
 #endif
-  CHelloWorld *pHelloWorld = new CHelloWorld;
 
+  // Exercise an explictly instantiated C++ object
+
+  CHelloWorld *pHelloWorld = new CHelloWorld;
   printf(MAIN_STRING "Saying hello from the dynamically constructed instance\n");
   pHelloWorld->HelloWorld();
 
+  // Exercise an C++ object instantiated on the stack
+
 #ifndef CONFIG_EXAMPLES_HELLOXX_NOSTACKCONST
+  CHelloWorld HelloWorld;
+
   printf(MAIN_STRING "Saying hello from the instance constructed on the stack\n");
   HelloWorld.HelloWorld();
 #endif
 
-#ifndef CONFIG_EXAMPLES_HELLOXX_NOSTATICCONST
+  // Exercise an statically constructed C++ object
+
+#ifdef CONFIG_HAVE_CXXINITIALIZE
   printf(MAIN_STRING "Saying hello from the statically constructed instance\n");
   g_HelloWorld.HelloWorld();
 #endif
-- 
cgit v1.2.3